DistanceMatrix.php
Immutable value object wrapping a validated symmetric distance matrix between taxa Freely inspired by BioPHP's project biophp.org Created 30 September 2026 Last modified 9 October 2026
Table of Contents
Classes
- DistanceMatrix
- Validates, once and for all at construction, every invariant NeighborJoiningTreeBuilder relies on : square, zero diagonal, symmetric, non-negative, unique non-empty labels. A distance is itself always non-negative by definition (it is a measurement, unlike the branch lengths the neighbor- joining algorithm later derives from it, which can legitimately go negative).